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Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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MYC threshold required to maintain tumor phenotype

ABSTRACT: We demonstrate that there is a level of MYC expression that is required for maintaining a tumor phenotype and at this threshold there is a switch from a state of cellular proliferation to a state of proliferative arrest and apoptosis. We analyzed changes in gene expression by oligonucleotide microarray analysis and quantitative PCR and found significant changes (FDR=5%) in 2348 down regulated genes and 1573 upregulated genes. Critical changes in gene expression that occurred at or near the threshold level of MYC expression includes genes that have been implicated in G1/S, G2/M cell cycle checkpoint pathways and death receptor/apoptosis signaling. Keywords: Dose response - MYC inactivation by doxycycline treatment 11 samples, replicates not included

ORGANISM(S): Mus musculus

SUBMITTER: Catherine Shachaf

PROVIDER: E-GEOD-10200 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Genomic and proteomic analysis reveals a threshold level of MYC required for tumor maintenance.

Shachaf Catherine M CM Gentles Andrew J AJ Elchuri Sailaja S Sahoo Debashis D Soen Yoav Y Sharpe Orr O Perez Omar D OD Chang Maria M Mitchel Dennis D Robinson William H WH Dill David D Nolan Garry P GP Plevritis Sylvia K SK Felsher Dean W DW

Cancer research 20080701 13

MYC overexpression has been implicated in the pathogenesis of most types of human cancers. MYC is likely to contribute to tumorigenesis by its effects on global gene expression. Previously, we have shown that the loss of MYC overexpression is sufficient to reverse tumorigenesis. Here, we show that there is a precise threshold level of MYC expression required for maintaining the tumor phenotype, whereupon there is a switch from a gene expression program of proliferation to a state of proliferativ ...[more]

PMID: 18593912

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MYC threshold required to maintain tumor phenotype

Project description:We demonstrate that there is a level of MYC expression that is required for maintaining a tumor phenotype and at this threshold there is a switch from a state of cellular proliferation to a state of proliferative arrest and apoptosis. We analyzed changes in gene expression by oligonucleotide microarray analysis and quantitative PCR and found significant changes (FDR=5%) in 2348 down regulated genes and 1573 upregulated genes. Critical changes in gene expression that occurred at or near the threshold level of MYC expression includes genes that have been implicated in G1/S, G2/M cell cycle checkpoint pathways and death receptor/apoptosis signaling. Keywords: Dose response - MYC inactivation by doxycycline treatment

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